The bond market thinks Warren Buffett is a safer investment than President Barack Obama.

Bloomberg analyzed the bonds of Buffett's Berkshire Hathaway Inc. along with other major businesses and found that investors wanted a slightly higher interest rate from government bonds.

That means investors think the government is a higher risk.

"It's a slap upside the head of the government," said Mitchell Stapley, the chief fixed-income officer in Grand Rapids, Michigan, at Fifth Third Asset Management, which oversees $22 billion. "It could be the moment where hopefully you realize that risk is beginning to creep into your credit profile and the costs associated with that can be pretty scary."

Government securities usually have the lowest rates, because they are considered so safe. However, the Obama administration is projected to add nearly $10 trillion in new federal debt in the next decade.

And that means Washington's credit rating could start to slip.

"America will use about 7 percent of taxes for debt payments in 2010 and almost 11 percent in 2013, moving "substantially" closer to losing its AAA rating," Moody's Investors Service said last week.